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bioRxiv · 10.1101/2023.08.28.554597

Glyco-Engineering Cell Surfaces by Exo-Enzymatic Installation of GlcNAz and LacNAz Motifs

De Leon Gonzalez, F. V.·Boddington, M. E.·Prindl, M. I.·Capicciotti, C. J.
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Abstract

Exo-enzymatic glyco-engineering of cell-surface glycoconjugates enables the selective display of well-defined glyco-motifs bearing bioorthogonal functional groups which can be used to study glycans and their interactions with glycan-binding proteins. While the installation of monosaccharides and their derivatives using glycosyltransferase enzymes has rapidly evolved, similar strategies to introduce chemical-reporter functionalized Type 2 LacNAc motifs have not been reported. Herein, we report the chemo-enzymatic synthesis of unnatural UDP-GlcNAc and UDP-GalNAc nucleotide-sugars, and the donor and acceptor substrate tolerance of the human glycosyltransferases B3GNT2 and B4GalT1, respectively, to form derivatized LacNAc moieties. We also demonstrate that B3GNT2 can be used to exo-enzymatically install GlcNAc and GlcNAz onto cell-surface glycans. GlcNAc- or GlcNAz-engineered cells can be further extended by B4GalT1, producing LacNAc or LacNAz-engineered cells. Our glyco-engineering labeling strategy is amenable to different cell types and our work expands the exo-enzymatic glycan editing toolbox to selectively introduce unnatural Type 2 LacNAc motifs.

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De Leon Gonzalez, F. V., Boddington, M. E., Prindl, M. I., Capicciotti, C. J.. 2023-08-29. Glyco-Engineering Cell Surfaces by Exo-Enzymatic Installation of GlcNAz and LacNAz Motifs. https://doi.org/10.1101/2023.08.28.554597

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